Chop saws and miter saws designed for cutting a workpiece are well known in the art. Referring to FIGS. 1–2, a miter saw 10 typically has a base 11, which may include a rotatable table 12 rotatably attached to base 11. A pivot arm 14 is pivotally attached to a trunnion 13, to allow a chopping function. Trunnion 13 in turn may be pivotally attached to the base 11 and/or table 12, to allow the trunnion 13 and pivot arm 14 to pivot relative to the base 11.
The pivot arm 14 carries a saw assembly which includes motor housing 20H, a motor 20M disposed in motor housing 20H, a blade 17 driven by motor 20M, an upper blade guard 15 covering an upper part of the blade 17, and a lower blade guard 16 pivotally attached to upper blade guard 15 for covering a lower part of the blade 17. A link 16L may connect lower blade guard 16 to trunnion 13 so that, as the saw assembly is pivoted downwardly to cut a workpiece disposed on base 11 and/or table 12, the lower blade guard 16 rotates and exposes the blade 17, as is well known in the art.
The pivot arm 14 may also carry a rear blade guard 21, which is typically made of metal.
A fence assembly 19 may be provided on both sides of blade 17. Persons skilled in the art are referred to the fence assemblies disclosed in U.S. Pat. Nos. 5,297,463 and 5,733,148, which are wholly incorporated herein by reference. Fence assembly 19 has a fixed fence 19F disposed on base 11, a movable fence 19M slidably disposed on fixed fence 19F, and a screw 19S for fixing the position of movable fence 19M relative to fixed fence 19F.
It is possible that when the user has beveled the saw assembly, i.e., pivoted the trunnion 13 relative to table 12, and pivots the saw assembly downwardly, the lower blade guard 16 or rear guard 21 may contact the movable fence 19M. Because the movable fence 19M typically has an inclined edge 19ME, the lower blade guard 16 and/or rear guard 21 may be forced into contact with blade 17, which could ultimately cut the lower blade guard 16 and/or rear guard 21.